The present invention relates to a fixing device for an adjustable steering column for a motor vehicle. The fixing device has a first cam carrier with one or more cams which are fastened fixedly thereto, and at least one further cam carrier with one or more cams which are fastened fixedly thereto. The cam carriers are arranged such that they can be rotated relative to one another about a rotational axis. During the rotation of the cam carriers relative to one another about the rotational axis, the cam or the cams of the first cam carrier interacting with the cam or the cams of the further cam carrier such that they slide exclusively along one another.
Cam-controlled fixing devices of the generic type for adjustable steering columns are known in a multiplicity of embodiments in the prior art. In fixing devices of the generic type, the cams are fastened fixedly on the cam carrier. The cams are usually configured in one piece with the base of the cam carrier. As a result of rotation of the cam carriers about the rotational axis, the cams of the cam carriers which correspond with one another slide along one another. As a result of the rotation and the design of the cams, a stroke occurs here in the longitudinal direction of the rotational axis, as a result of which the fixing device is moved from an open position into a closed position or vice versa. The range, in which the cams can be rotated with respect to one another, the rotating range, is delimited by the rotational position of the two cams in the open position and the rotational position of the two cams in the closed position. In the open position, the adjustable steering column can be adjusted in order to adapt the position of the steering wheel to the respective driver. In the closed position of the fixing device, the position of the steering wheel is fixed.
A fixing device of the generic type is known, for example, from EP 1 795 425 A2. There, elastic tongues are provided which serve to stress the two cam carriers elastically onto one another in order to reduce the play in the axial direction of the rotational axis.
In fixing devices of the generic type, the cams move exclusively slidingly along one another. A rolling movement or the like therefore does not occur. As a result of the cams sliding along one another of the participating cam carriers, a certain damping action of the movement during rotation of the cam carriers with respect to one another already automatically occurs in fixing devices of the generic type.